初始提交: Gitea 项目代码

models/db/iterate.go

@@ -0,0 +1,43 @@
+// Copyright 2022 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package db
+
+import (
+	"context"
+
+	"gitea.dev/modules/setting"
+
+	"xorm.io/builder"
+)
+
+// Iterate iterates all the Bean object
+func Iterate[Bean any](ctx context.Context, cond builder.Cond, f func(ctx context.Context, bean *Bean) error) error {
+	var start int
+	batchSize := setting.Database.IterateBufferSize
+	sess := GetEngine(ctx)
+	for {
+		select {
+		case <-ctx.Done():
+			return ctx.Err()
+		default:
+			beans := make([]*Bean, 0, batchSize)
+			if cond != nil {
+				sess = sess.Where(cond)
+			}
+			if err := sess.Limit(batchSize, start).Find(&beans); err != nil {
+				return err
+			}
+			if len(beans) == 0 {
+				return nil
+			}
+			start += len(beans)
+
+			for _, bean := range beans {
+				if err := f(ctx, bean); err != nil {
+					return err
+				}
+			}
+		}
+	}
+}